Fuel-conditioning system



March 20, 1928,

c SCHWARTZ FUEL counmomne SYSTEM Filed March 11. 1924 INVENTOR Q-MW ATTORNEYJ ill Patented Mar. 20, 1928.

' UNITED TENT "FFIc.

CARL SCHWARTZQOF 'Nnw RocI' ELLE, NEW YORK, ASSIGNOR To'INTEnNA IoNA iCOMBUSTION ENGINEERING CORPORATION, A COBLPGRATION or DELAWARE.

- FUiEL-CQNDITIONING SYSTEM,

Applicationfiled March 1-1, 1924. Serial No. 698,411.

This invention relates to a conditioning systen'i and it is especiallyuseful in connection with pulverized coal burning installa tions,particularly those. of the 'direct fired Y type in which the coal is ledfrom the pulverizer to the furnace.

In such direct fired arrangements the coal mixed with air is conveyed tothe burners from the pulverizerand'the operation of thepulverizer isimpaired by virtue of the relatively large volume of air which is passedtherethrough and, in addition, the passage of this air through thepulverizer represents work more or less uselessly performed, in; volvingincreased power costs and larger and more. expensive motors andapparatus. The mixture, also, is not uniform, which is an item ofconsiderable importance. Deficiencies in mixture cannot be wholly andeffectively compensated for by air admission at the furnace.

I aim to overcome these difficulties and to make direct firing-morepractical and effective. I contemplate the proper conditioning of thefuel intermediate the pulverizer or other source of supply and the pointof use, so that on the one hand, I may decrease power costs and the sizeof the pulverizer equipment and increase the effectiveness of thepulverizer and on the other hand burn the fuel more effectively and withless complication as to air supply and regulation.

More specifically, it is an object of my in- ;yention to provide asimple, effective conditioning apparatus, inexpensive to operate andmaintain.

How the foregoing, together with such other objects as may hereinafterappear, or are incident to my invention, are obtained, I have disclosedin the following description and illustrated in preferred form in thedrawing which is a diagrammatic illustration of my invention.

lVith reference to the drawing, the conditioner comprises a vessel ortank 7 and a means for maintaining the fuel in suspen sion in airtherein and in circulation. The pulverized fuel is led directly to thetank from the pulverizer (not shown) with practically only carrying airthrough the branch pipe 8 and the pipe 9, which latter is provided witha feeder 10 of any preferred design such as the star wheel type shown;or from a storage tank through the damper controlled branch 8. Thisfeeder is preferably operated at speeds such as will replace fuel asfast as drawn form the conditioningtank to the furnace- Leading form thetank, preferably the up per part thereof, is a pipe 11 which entersanother part, preferably-the bottom, and extends well within the tankwhere it'is provided with a plurality of upwardly directed nozzle or jetopenings 12. Located in'this pipe is a suction fan 13. The operation ofthis fan, in starting, by way of illustration,-

is to'draw air from the upper part of the tank and discharge it upwardlyin the bottom of thetank, putting the pulverized coal in suspension inair. As the operation continues, the fan drawsa mixture of coal and airfrom the top and discharges it into the bottom, keeping the fuel insuspension and in circulation. The fan may be small and uses littlepower as the operation is at atmospheric pressure, i. e. neither plusnor minus.

A stream of the mixture may be drawn ofl at will through an outletconduit or pipe 14, of which there may be one for each burner 15. Thisoutlet preferably leads from an intermediate or middle portion of thetank,

the intake end 14L being turned downwardly to more effectively carry offthe mixture. Any preferred arrangement may be employed to induce a flowthrough the pipe 14 and, in this instance, I have shown a fan 16,although other means may be well substituted.

As the stream is being drawn off, make up air is admitted through theinlet 17, which may well be merely open to the atmosphere, as the actionwill be substantially automatic for the reason that the feeder suppliesfuel at the rate that the fuel is drawn out; and hence air enters 17 atthe rate that it is drawn out. Stated another way the feeder and pipe 17together supply coal and air at the rate coal and air are drawn off. A

damper 18 is provided for control if needed.

sign of the parts. With a uniform mixture and a uniform feed, which alsoresults, the burning of the fuel may be more effectively accomplished,and the regulation of additional air admitted to the furnace forcombustion simplified.

In shutting down, the damper 19 is closed and the damper 20 opened,whereby air is admitted to the pipe 14 and all feel drawn out therewith,leaving the pipe clean for starting up.

I claim: 1. In a pulverized fuel conditioning system, the combination ofa source of fuel supply, a point of use, an interposed conditioningvessel having a fuel and air circulator adapted to maintain a mixture ofthe fuel with the air in the vessel, and a separate air inlet leadingfrom the atmosphere to the conditioning vessel independent of thecirculator. V

2. In a pulverized fuel conditioning system, the combination of a sourceof fuel supply, a point of use, an interposed conditioning apparatuswith connections from the supply means and to the point of use, and

means whereby one of the connections may be exhausted of its contents.

3. In a pulverized fuel conditioning system, a source of supply, a pointof use, and

in an upper region thereof; a fuel and air mixerincluding a conduit withfuel and air circulating means therein, one end of said conduit beingconnected into the chamber for the withdrawal of air and fuel therefrom,and the other end extending into the lower part of said chamber andhaving a plurality of upwardly directed discharge:

openings; and an outlet from the chamber for the mixed fuel and air.

In testimony whereof, I have hereunto signed my name.

CARL: SCHWARTZ 1

